The smallest unit of genetic material which,when altered,results in a mutation is known as .....

Statement $P$: $m-RNA$ contains $75$ nucleotides.
Statement $Q$: There are $20$ types of $t-RNA$ in the cytoplasm.

Which of the following is not a correct statement regarding $\text{RNA}$?

Match the following:

Column-$I$	Column-$II$
$(1)$ Ligase	$(p)$ Segment of $DNA$
$(2)$ $RNA$ polymerase + Rho factor	$(q)$ Replication
$(3)$ $RNA$ polymerase	$(r)$ Termination
$(4)$ Cistron	$(s)$ Elongation

The one-gene-one-enzyme relationship was first established in.....

Read the following statements carefully and choose the correct statements.
$(A)$ In a transcription unit,the promoter is located at the $5'$ end of the coding strand.
$(B)$ The single strand $DNA$ having the polarity $5' \rightarrow 3'$ is the template strand.
$(C)$ $RNA$ polymerase binds to the operator during transcription.
$(D)$ Single base $DNA$ differences occurring in humans are called Single Nucleotide Polymorphisms $(SNPs)$.